Journalists stand near a bullet-ridden van during Tuesday's attack in Kabul.

Daud YardostAFP/Getty Images

Insurgents rained a barrage of rockets and gunfire on the U.S. Embassy and NATO headquarters Tuesday in a brazen attack in Afghanistan's capital that underscores their ability to stage operations even as coalition forces hand over security to Afghan troops.

The militants launched the high-profile assault just two days after the U.S. marked the 10th anniversary of the Sept. 11 terrorist attacks. It was the third major strike in Kabul since late June, casting fresh doubts on the ability of Afghans to secure their own country as the U.S. and other foreign troops prepare to withdraw by the end of 2014.

The Taliban claimed responsibility for the assault.

Loud Blasts And Gunfire

It began with a series of explosions that witnesses said enabled fighters to get into a nine-story building under construction in Abdul Haq square, about 300 yards from the U.S. Embassy. The gunmen then began firing down on the embassy, NATO headquarters and an American military base.

"It's a very tall building with a line of sight across all of the NATO headquarters, as well as the U.S. Embassy," NPR's Quil Lawrence reported from a nearby rooftop in central Kabul. He said the insurgents seemed "to have a great command of the surrounding area."

The diplomatic compounds are located in Wazir Akhabar Khan, one of Kabul's most heavily secured neighborhoods. That part of the city has been under Afghan security control since this summer.

U.S. Embassy spokeswoman Kerri Hannan issued a statement confirming an attack by gunmen firing rocket-propelled grenades and small arms fire.

"We can confirm there are no casualties at this time among embassy personnel," she said.

One rocket-propelled grenade hit behind a minivan carrying schoolchildren, while another landed on a building housing privately owned Tolo TV. After an hour of sustained gunfire, U.S. special forces in helicopters arrived and exchanged fire with the insurgents in the building site, Lawrence said.

He said he could hear the sound of "steady but sporadic fire" amid alert sirens from the U.S. Embassy, where people were warned over the PA system to stay under cover. The compound also is home to a number of other foreign missions.

Police Seal Off Parts Of Kabul

"There are Afghan soldiers and Afghan anti-terrorism personnel all over the streets," Lawrence said. He added that police had cordoned off a large section of the city.

Miles away in western Kabul, suicide bombers tried to attack police buildings in what appeared to be a synchronized strike, The Associated Press reported.

Kabul police said at least seven insurgents were involved in attacks around the city. Four were involved in the attack from the building, and three attempted to carry out suicide attacks. They said at least one Afghan police officer, a civilian, and two insurgents had been killed as gunfire and explosions resounded across the city well into the afternoon.

The Interior Ministry said nine people were wounded around the capital.

NATO: Attack Meant To Disrupt Security Transfer

In Brussels, NATO Secretary-General Anders Fogh Rasmussen said the "enemies of Afghanistan" were trying to disrupt the handing over of security responsibility to the Afghan army and police.

He said Afghan forces were already taking the lead for security in several provinces and districts that were home to a quarter of the population.

"Afghan security forces are growing both in numbers and quality, and I am confident they will take the lead for security throughout the country by the end of 2014 as we all agreed," Rasmussen said.

CIA Director David Petraeus said the attacks were carried out by "a handful of attackers, five or so, apparently armed with suicide vests."

Speaking at the State Department, Secretary of State Hillary Clinton called it a "cowardly attack" and said steps would be taken "to ensure that those who perpetrated this attack are dealt with." The White House said that President Obama had been briefed on the situation.

Taliban spokesman Zabiullah Mujahid said a number of suicide bombers were attacking Afghan and foreign soldiers at the square. He claimed in a text message that suicide bombers using assault rifles were attacking the offices of the Afghan intelligence service.

Recent Surge In Attacks

Violence in the once-quiet capital has escalated in recent months.

On Aug. 18, Taliban suicide bombers stormed a British compound in an upscale Kabul neighborhood, killing eight people during an eight-hour firefight as two English-language teachers and their bodyguard hid in a locked panic room. Those killed included five policemen, a municipal worker, a security guard and a New Zealand special forces soldier who was shot in the chest as he tried to free the hostages — who survived.

On June 29, nine insurgents wearing suicide vests stormed the Intercontinental Hotel armed with rifles and rocket launchers on the eve of a major conference on Afghan governance. They killed at least 12 people and held off NATO and Afghan forces for five hours, until U.S.-launched helicopter strikes killed the last insurgents hiding on the roof.

NPR's Quil Lawrence and Renee Montagne reported from Kabul, Afghanistan, for this story, which contains material from The Associated Press.

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